// (c) Copyright Ascensio System SIA 2010-2022
//
// This program is a free software product.
// You can redistribute it and/or modify it under the terms
// of the GNU Affero General Public License (AGPL) version 3 as published by the Free Software
// Foundation. In accordance with Section 7(a) of the GNU AGPL its Section 15 shall be amended
// to the effect that Ascensio System SIA expressly excludes the warranty of non-infringement of
// any third-party rights.
//
// This program is distributed WITHOUT ANY WARRANTY, without even the implied warranty
// of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For details, see
// the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
//
// You can contact Ascensio System SIA at Lubanas st. 125a-25, Riga, Latvia, EU, LV-1021.
//
// The  interactive user interfaces in modified source and object code versions of the Program must
// display Appropriate Legal Notices, as required under Section 5 of the GNU AGPL version 3.
//
// Pursuant to Section 7(b) of the License you must retain the original Product logo when
// distributing the program. Pursuant to Section 7(e) we decline to grant you any rights under
// trademark law for use of our trademarks.
//
// All the Product's GUI elements, including illustrations and icon sets, as well as technical writing
// content are licensed under the terms of the Creative Commons Attribution-ShareAlike 4.0
// International. See the License terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode

namespace TMResourceData;

public class DBResourceManager : ResourceManager
{
    public static readonly bool WhiteLableEnabled;
    private readonly ConcurrentDictionary<string, ResourceSet> _resourceSets = new ConcurrentDictionary<string, ResourceSet>();
    private readonly IMemoryCache _memoryCache;

    public DBResourceManager(string filename, Assembly assembly)
                : base(filename, assembly)
    {
    }

    public DBResourceManager(
        IMemoryCache memoryCache,
        IConfiguration configuration,
        ILogger<DBResourceManager> option,
        DbContextManager<ResourceDbContext> dbContext,
        string filename,
        Assembly assembly)
                : base(filename, assembly)
    {
        _memoryCache = memoryCache;
        _configuration = configuration;
        _option = option;
        _dbContext = dbContext;
    }

    public static void PatchAssemblies(ILogger<DBResourceManager> option)
    {
        AppDomain.CurrentDomain.AssemblyLoad += (_, a) => PatchAssembly(option, a.LoadedAssembly);
        Array.ForEach(AppDomain.CurrentDomain.GetAssemblies(), a => PatchAssembly(option, a));
    }

    public static void PatchAssembly(ILogger<DBResourceManager> logger, Assembly a, bool onlyAsc = true)
    {
        var log = logger;

        if (!onlyAsc || Accept(a))
        {
            var types = Array.Empty<Type>();
            try
            {
                types = a.GetTypes();
            }
            catch (ReflectionTypeLoadException rtle)
            {
                log.CanNotGetType(nameof(a.GetType), a.FullName, nameof(a.GetExportedTypes), rtle);
                foreach (var e in rtle.LoaderExceptions)
                {
                    log.Information(e.Message);
                }

                try
                {
                    types = a.GetExportedTypes();
                }
                catch (Exception err)
                {
                    log.CanNotGetExportedTypes(a.FullName, nameof(a.GetExportedTypes), err);
                }
            }
            foreach (var type in types)
            {
                var prop = type.GetProperty("ResourceManager", BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public);
                if (prop != null)
                {
                    var rm = (ResourceManager)prop.GetValue(type);
                    if (rm is not DBResourceManager)
                    {
                        var dbrm = new DBResourceManager(rm.BaseName, a);
                        type.InvokeMember("resourceMan", BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.SetField, null, type, new object[] { dbrm });
                    }
                }
            }
        }
    }

    private static bool Accept(Assembly a)
    {
        var n = a.GetName().Name;

        return (n.StartsWith("ASC.") || n.StartsWith("App_GlobalResources")) && a.GetManifestResourceNames().Length > 0;
    }

    public override Type ResourceSetType => typeof(DBResourceSet);

    private readonly IConfiguration _configuration;
    private readonly ILogger<DBResourceManager> _option;
    private readonly DbContextManager<ResourceDbContext> _dbContext;

    protected override ResourceSet InternalGetResourceSet(CultureInfo culture, bool createIfNotExists, bool tryParents)
    {
        _resourceSets.TryGetValue(culture.Name, out var set);
        if (set == null)
        {
            var invariant = culture == CultureInfo.InvariantCulture ? base.InternalGetResourceSet(CultureInfo.InvariantCulture, true, true) : null;
            set = new DBResourceSet(_memoryCache, _configuration, _option, _dbContext, invariant, culture, BaseName);
            _resourceSets.AddOrUpdate(culture.Name, set, (k, v) => set);
        }

        return set;
    }

    class DBResourceSet : ResourceSet
    {
        private const string NeutralCulture = "Neutral";

        private readonly TimeSpan _cacheTimeout = TimeSpan.FromMinutes(120); // for performance
        private readonly object _locker = new object();
        private readonly IMemoryCache _cache;
        private readonly ResourceSet _invariant;
        private readonly string _culture;
        private readonly string _fileName;
        private readonly ILogger<DBResourceManager> _logger;
        private readonly DbContextManager<ResourceDbContext> _dbContext;

        public DBResourceSet(
            IMemoryCache memoryCache,
            IConfiguration configuration,
            ILogger<DBResourceManager> logger,
            DbContextManager<ResourceDbContext> dbContext,
            ResourceSet invariant,
            CultureInfo culture,
            string filename)
        {
            ArgumentNullException.ThrowIfNull(culture);
            ArgumentNullOrEmptyException.ThrowIfNullOrEmpty(filename);

            _dbContext = dbContext;
            _logger = logger;

            try
            {
                var defaultValue = ((int)_cacheTimeout.TotalMinutes).ToString();
                _cacheTimeout = TimeSpan.FromMinutes(Convert.ToInt32(configuration["resources:cache-timeout"] ?? defaultValue));
            }
            catch (Exception err)
            {
                _logger.ErrorDBResourceSet(err);
            }

            _invariant = invariant;
            _culture = invariant != null ? NeutralCulture : culture.Name;
            _fileName = filename.Split('.').Last() + ".resx";
            _cache = memoryCache;
        }

        public override string GetString(string name, bool ignoreCase)
        {
            var result = (string)null;
            try
            {
                var dic = GetResources();
                dic.TryGetValue(name, out result);
            }
            catch (Exception err)
            {
                _logger.CanNotGetResource(_fileName, _culture, name, err);
            }

            if (_invariant != null && result == null)
            {
                result = _invariant.GetString(name, ignoreCase);
            }

            return result;
        }

        public override IDictionaryEnumerator GetEnumerator()
        {
            var result = new Hashtable();
            if (_invariant != null)
            {
                foreach (DictionaryEntry e in _invariant)
                {
                    result[e.Key] = e.Value;
                }
            }
            try
            {
                var dic = GetResources();
                foreach (var e in dic)
                {
                    result[e.Key] = e.Value;
                }
            }
            catch (Exception err)
            {
                _logger.ErrorDBResourceSet(err);
            }

            return result.GetEnumerator();
        }

        private Dictionary<string, string> GetResources()
        {
            var key = $"{_fileName}/{_culture}";
            if (_cache.Get(key) is not Dictionary<string, string> dic)
            {
                lock (_locker)
                {
                    dic = _cache.Get(key) as Dictionary<string, string>;

                    if (dic == null)
                    {

                        dic = LoadResourceSet(_fileName, _culture);

                        if (_cacheTimeout == TimeSpan.Zero)
                        {
                            _cache.Set(key, dic);
                        }
                        else
                        {
                            _cache.Set(key, dic, DateTimeOffset.Now.Add(_cacheTimeout));
                        }

                    }
                }
            }

            return dic;
        }

        private Dictionary<string, string> LoadResourceSet(string filename, string culture)
        {
            using var context = _dbContext.Get("tmresource");
            var q = context.ResData
                .Where(r => r.CultureTitle == culture)
                .Join(context.ResFiles, r => r.FileId, a => a.Id, (d, f) => new { data = d, files = f })
                .Where(r => r.files.ResName == filename);

            return q
                .ToDictionary(r => r.data.Title, r => r.data.TextValue, StringComparer.InvariantCultureIgnoreCase);
        }
    }
}

[Singletone]
public class WhiteLabelHelper
{
    private readonly ILogger _logger;
    private readonly ConcurrentDictionary<int, string> _whiteLabelDictionary;
    public string DefaultLogoText { get; set; }

    private readonly IConfiguration _configuration;

    public WhiteLabelHelper(IConfiguration configuration, ILoggerProvider option)
    {
        _logger = option.CreateLogger("ASC.Resources");
        _whiteLabelDictionary = new ConcurrentDictionary<int, string>();
        DefaultLogoText = string.Empty;
        _configuration = configuration;
    }

    public void SetNewText(int tenantId, string newText)
    {
        try
        {
            _whiteLabelDictionary.AddOrUpdate(tenantId, r => newText, (i, s) => newText);
        }
        catch (Exception e)
        {
            _logger.ErrorSetNewText(e);
        }
    }

    public void RestoreOldText(int tenantId)
    {
        try
        {
            _whiteLabelDictionary.TryRemove(tenantId, out var text);
        }
        catch (Exception e)
        {
            _logger.ErrorRestoreOldText(e);
        }
    }

    internal string ReplaceLogo(TenantManager tenantManager, IHttpContextAccessor httpContextAccessor, string resourceName, string resourceValue)
    {
        if (string.IsNullOrEmpty(resourceValue))
        {
            return resourceValue;
        }
        if (!DBResourceManager.WhiteLableEnabled)
        {
            return resourceValue;
        }

        if (httpContextAccessor.HttpContext != null) //if in Notify Service or other process without HttpContext
        {
            try
            {
                var tenant = tenantManager.GetCurrentTenant(false);
                if (tenant == null)
                {
                    return resourceValue;
                }

                if (_whiteLabelDictionary.TryGetValue(tenant.Id, out var newText))
                {
                    var newTextReplacement = newText;

                    if (resourceValue.IndexOf('<') >= 0 && resourceValue.IndexOf('>') >= 0 || resourceName.StartsWith("pattern_"))
                    {
                        newTextReplacement = HttpUtility.HtmlEncode(newTextReplacement);
                    }
                    if (resourceValue.Contains("{0"))
                    {
                        //Hack for string which used in string.Format
                        newTextReplacement = newTextReplacement.Replace("{", "{{").Replace("}", "}}");
                    }

                    var replPattern = _configuration["resources:whitelabel-text.replacement.pattern"] ?? "(?<=[^@/\\\\]|^)({0})(?!\\.com)";
                    var pattern = string.Format(replPattern, DefaultLogoText);
                    //Hack for resource strings with mails looked like ...@onlyoffice... or with website http://www.onlyoffice.com link or with the https://www.facebook.com/pages/OnlyOffice/833032526736775

                    return Regex.Replace(resourceValue, pattern, newTextReplacement, RegexOptions.IgnoreCase).Replace("™", "");
                }
            }
            catch (Exception e)
            {
                _logger.ErrorReplaceLogo(e);
            }
        }

        return resourceValue;
    }
}